Typically, a wireless communication system has been developed to provide voice services while ensuring the mobility of users. However, the wireless communication system has been expanded from the voice service to a data service. In recent years, the wireless communication system has been developed to provide a high-speed data service. However, currently, the wireless communication system that provides services suffers from a lack of resources, and users require the wireless communication system to provide higher-speed services to them. Accordingly, there is a necessity for more advanced wireless communication systems.
In the same context, an amount of average data which is used by users of the wireless communication system has been increasing geometrically owing to the use of a wireless terminal, such as a smart phone. In addition to that, users' demands for a higher data transmission rate have been continuously increasing.
In general, a method of providing a high data transmission rate includes a method of providing a communication using a wider frequency band and a method of increasing frequency usage efficiency.
However, it is very difficult to provide a higher average data transmission rate through the latter method. This is because communication technologies of a current generation provide frequency usage efficiency close to a theoretical limit and thus, it is very difficult to increase the frequency usage efficiency up to that or more through a technical improvement.
Accordingly, it can be said that a feasible method for increasing the data transmission rate is a method of providing data services through the wider frequency band. At this time, the thing to consider is an available frequency band. In view of the current frequency distribution policy, a band in which a broadband communication of 1 GHz or more is possible is limited and a practically selectable frequency band is the millimeter wave band of 30 GHz or more.
Such a signal of the high frequency band causes severe signal attenuation according to a distance differently from a signal of a frequency band of 2 GHz used by the cellular systems of the related art. Due to such signal attenuation, a coverage area providing service of a base station using the same power as the cellular systems of the related art is considerably reduced. In order to address this issue, a beamforming technique is widely used which concentrates transmission/reception power into a narrow space to increase transmission/reception efficiency of an antenna.
To meet the demand for wireless data traffic having increased since deployment of 4G communication systems, efforts have been made to develop an improved 5G or pre-5G communication system. Therefore, the 5G or pre-5G communication system is also called a ‘Beyond 4G Network’ or a ‘Post LTE System’.
The 5G communication system is considered to be implemented in higher frequency (mmWave) bands, e.g., 60 GHz bands, so as to accomplish higher data rates. To decrease propagation loss of the radio waves and increase the transmission distance, the beamforming, massive multiple-input multiple-output (MIMO), Full Dimensional MIMO (FD-MIMO), array antenna, an analog beam forming, large scale antenna techniques are discussed in 5G communication systems.
In addition, in 5G communication systems, development for system network improvement is underway based on advanced small cells, cloud Radio Access Networks (RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), reception-end interference cancellation and the like.
In the 5G system, Hybrid FSK and QAM Modulation (FQAM) and sliding window superposition coding (SWSC) as an advanced coding modulation (ACM), and filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as an advanced access technology have been developed.
However, in a wireless communication system supporting the beamforming of the related art, optimum analog beams (e.g., a Tx beam ID) according to each array antenna should be selected, a digital precoding vector applied to a signal connected to a plurality of array antennas should be determined. However, a delay may occur, owing to the time taken processing these selections and the determination.
Therefore, a need exists for a method and an apparatus for reducing a feedback delay in a wireless communication system based on a superhigh frequency beamforming technique.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.